10 value card in the deck game. Letter jota . Joule symbol (Unit of measurement of energy: the work done by a force of one newton in a displacement of one meter in the direction of the force).
1º_ Letter jota . 2º_ 'J' is the symbol of the joule ("unit of measurement for energy, work and heat"). 3º_ 'J' represents the Jack (value 10) in the French or English deck.
J: letter which formerly amounted to T, Holland.